Black Box RS-232485/422 Converter Plus, RS-232485/422 Opto-Isolator/Converter, IC109C, IC108A manual

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RS-232485/422 CONVERTERS

Table 2 (continued). DTE Jumper Settings.

Function

Jumper Requirements

 

 

 

9. RS-485 Interface Line Biased (Fail-

S3 Off

No line bias

Safe), Receive

 

 

 

S3 On

Line biased

 

 

 

NOTE

If line bias is on, the RS-485 CD will ALWAYS be on.

3.3 Typical Applications

This section describes some typical applications where the RS-232485/422 Converter might be used. The connections shown in the figures are for the RS-485 port.

Figure 5 shows a typical point-to-point, 4-wire, full- or half-duplex connection with both RS-232485/422 Converters terminated by setting switch S2 to the TERM position. Figure 6 shows a typical point-to-point, 2-wire, half-duplex connection with both RS-232485/422 Converters terminated by setting switch S2 to the TERM position.

In a 4-wire, point-to-point application, each of the drivers on the two RS-232485/422 Converters may always be enabled without any adverse effects.

In a 2-wire, point-to-point or multipoint application, only one driver may be enabled at any one time. If more than one driver is turned ON, a situation known as contention occurs and the data from one driver interferes with the data from the other driver. This results in both sets of data being unintelligible.

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Contents IC109AE FCC and IC RFI Statements RS-232↔485/422 Converters NOM Statement Trademarks Used in this Manual Contents Specifications Specifications Introduction Jumper and Switch Configuration InstallationLayout of the Printed Circuit Board RS-232↔485/422 Converter as DCE XW1A 8-Position Shunt Driver Enabled by Data Point-to-Point DCE/DTE Configuration Function Jumper Requirements RS-232↔485/422 Converters Installation RS-232↔485/422 Converters Simplified Functional Block Diagram DTE Operation DTE Jumper Settings Installation Typical Applications Point-To-Point, 4-Wire Full- or Half-Duplex Multipoint, 4-Wire Half- or Full-Duplex Multipoint, 2-Wire Half-Duplex Sample Multipoint Operation Installation DCE DTE Appendix A. PinningPin Name Description XW1B Quick Reference User-Selectable OptionsQuick Reference USER-SELECTABLE Options Copyright 2002. Black Box Corporation. All rights reserved